SSL Certificate Generation

Now we will show how to generate server and client side certificates for the FTP service using OpenSSL. OpenSSL is a widely used and versatile open-source software library and toolkit for implementing Secure Sockets Layer (SSL) and Transport Layer Security (TLS) protocols. It provides a set of cryptographic functions and tools that enable secure communication and data encryption over computer networks, particularly the internet.

We will generate a root certificate authority (CA) certificate and key, as well as server and client certificates and keys. These certificates and keys are essential for establishing secure SSL/TLS connections in our FTP service. The root CA certificate establishes trust, and the server and client certificates allow secure communication while identifying themselves to each other.

Generating SSL/TLS certificates

We will use command-line instructions for generating the certificates and keys for secure communication using OpenSSL.

Root certificate (rootCAKey.pem and rootCACert.pem)

The root private key is the most critical component in establishing trust within a public key infrastructure (PKI). It is used to create and sign certificates. The root certificate authority (CA) uses this private key to sign its own certificate. This self-signed certificate serves as the ultimate trust anchor in the PKI.

Step 1: We will generate a 2048-bit RSA private key and store it as rootCAKey.pem by running the command:

• genrsa is the OpenSSL command for generating an RSA private key.

• -out specifies the output file where the generated private key will be stored. In this case, it is named rootCAKey.pem.

• 2048 specifies the key size, indicating that a 2048-bit RSA key will be generated.

Step 2: Next step is to generate a self-signed root certificate rootCACert.pem using the private key generated above. The certificate is generated using the following command: